In this age of safety awareness, technological emergencies still happen, occasionally with catastrophic results. Often human intervention is the only way of averting disaster. Ensuring that the chosen emergency managers are competent requires a combination of training and assessment. However, assessment currently relies on expert judgement of behaviour as opposed to its impact on outcome, therefore it would be difficult to incorporate such data into formal Quantitative Risk Assessments (QRA). Although there is, as yet, no suitable alternative to expert judgement, there is a need for methods of quantifying the impact of emergency management on risk reduction in accident and incidents. The Task Performance Resource Constraint (TPRC) model is capable of representing the critical factors. It calculates probability of task success with respect to time based on uncertainties associated with the task and resource variables. The results can then be used to assess the management performance based on the physical outcome in the emergency, thereby providing a measure of the impact of emergency management on risk with a high degree of objectivity. Data obtained from training exercises for offshore and onshore emergency management were measured and successfully used with the TPRC model. The resulting probability of success functions also demonstrated a high level of external validity when used with improvements in emergency management or design changes or real data from the Piper Alpha disaster. It also appeared to have more external validity than other HRQ/QRA techniques as it uses physical data that are a greater influence on outcome than psychological changes - though this could be because the current HRA/QRA techniques view human unreliability as probability of error rather than probability of failure. The simulation data were also used to build up distributions of timings for simple emergency management tasks. Using additional theoretical data, this demonstrated the model's potential for assessing the probability of successf or novel situations and future designs.

Master of Science / Department of Industrial & Manufacturing Systems Engineering / Malgorzata J. Rys / According to the Centers for Disease Control and Prevention (2015), urinary tract infections (UTIs) are the most commonly reported healthcare-associated infection (HAI), of which approximately 75% of infections are attributed to the presence of a urinary catheter. Urinary catheters are commonplace within hospitals as approximately 15-25% of patients receive a urinary catheter during their hospitalization, introducing the risk of a catheter associated urinary tract infection (CAUTI) during their stay (CDC, 2015). In recent years there have been efforts to reduce CAUTI in U.S. hospitals; however, despite these efforts, CAUTI rates indicate the need to continue prevention efforts. Researchers have investigated the use of human reliability analysis (HRA) techniques to predict and prevent CAUTI (Griebel, 2016), and this research builds on that topic by applying the Human Error Assessment and Reduction Technique (HEART) to develop a model for a patient’s probability of CAUTI. HEART considers 40 different error-producing conditions (EPCs) present while performing a task, and evaluates the extent to which each EPC affects the probability of an error. This research considers the task of inserting a Foley catheter, where an error in the process could potentially lead to a CAUTI. Significant patient factors that increase a patient’s probability of CAUTI (diabetes, female gender, and catheter days) are also considered, along with obesity which is examined from a process reliability perspective. Under the HEART process, human reliability knowledge and the knowledge of eight expert healthcare professionals are combined to evaluate the probability that a patient will acquire a CAUTI. In addition to predicting the probability of CAUTI, HEART also provides a systematic way to prioritize patient safety improvement efforts by examining the most significant EPCs or process steps. The proposed CAUTI model suggests that 7 of the 26 steps in the catheter insertion process contribute to 95% of the unreliability of the process. Three of the steps are related to cleaning the patient prior to inserting the catheter, two of the steps are directly related to actually inserting the catheter, and two steps are related to maintaining the collection bag below the patient’s bladder. An analysis of the EPCs evaluated also revealed that the most significant factors affecting the process are unfamiliarity, or the possibility of novel events, personal psychological factors, shortage of time, and inexperience. By targeting reliability improvements in these steps and factors, healthcare organizations can have the greatest impact on preventing CAUTI.

The presented doctoral thesis is focused on assessment of human factor impact on safety of industrial furnaces. Industrial furnaces are classified as machinery and belong to a group of industrial thermal equipment. The operation of industrial furnaces is burdened with the risks which the manufacturers and the furnace operators realize. The first part of the thesis presents an analysis of the current situation of legislation and scientific knowledges in the field of assessment of human factor impact on safety of industrial furnaces. In this part of the thesis the issue of human factor in other industrial branches: chemical industry, aviation and nuclear industry is also described. On the basis of conducted research the main aim of the thesis was established: preparation of a methodology for assessment of human factor impact on safety of industrial furnaces. Secondary targets were also listed. The second part deals with the assessment of risks connected with the operation of industrial furnaces and the assessment of human factor impact on safety of industrial furnaces. The furnace safety requirements, the process of furnaces risk assessment, the methods used for risk assessment and problems connected with the risk assessment are described. This part of the thesis explains the concept of human factor, presents a classification and description of the methods used for human reliability assessment, as well as the factors influencing the reliability of the operator. The third part of the thesis contains a proposed methodology for assessment of human factor impact on safety of industrial furnaces. Within the methodology performance shaping factors are stated, qualitative and quantitative assessment of human factor impact on safety of industrial furnaces is made and the system integration of the knowledges into the developed methodology is proposed – qualitative model for improvement of system state. The methodology is further verified on a real equipment – a hardening furnace.